add rollup for maplibre

Makefile

@@ -110,6 +110,7 @@ govukAssets::
 	npx nps copy.govukAssets
 
 javascripts:
+	npm run build
 	rsync -r assets/javascripts static/
 
 robots:

application/templates/national-map.html

@@ -14,7 +14,7 @@
 %}
 
 {%- block mapAssets %}
-  <script src='https://unpkg.com/maplibre-gl@latest/dist/maplibre-gl.js'></script>
+  <script src='/static/javascripts/maplibre-gl.js'></script>
   <link href='https://unpkg.com/maplibre-gl@latest/dist/maplibre-gl.css' rel='stylesheet' />
   {{ super() }}
 {% endblock -%}

package.json

@@ -31,13 +31,14 @@
     "test": "vitest run",
     "coverage": "vitest run --coverage",
     "test-unit": "vitest run --dir tests/unit/javascript",
-    "test-integration": "vitest run --dir tests/integration/javascript"
+    "test-integration": "vitest run --dir tests/integration/javascript",
+    "build": "rollup -c"
   },
   "dependencies": {
     "copyfiles": "^2.4.1",
     "govuk-frontend": "4.2.0",
-    "node-sass": "^9.0.0",
-    "nps": "^5.10.0"
+    "maplibre-gl": "^4.1.2",
+    "node-sass": "^9.0.0"
   },
   "devDependencies": {
     "@vitest/coverage-v8": "^0.34.1",

rollup.config.js

@@ -0,0 +1,10 @@
+// get the config object from the package file
+module.exports = [
+  {
+    input: `./node_modules/maplibre-gl/dist/maplibre-gl.js`,
+    output: {
+      file: `static/javascripts/maplibre-gl.js`,
+      format: "iife",
+    }
+  },
+];